Download or read book Effect of Body Weight and Age at Calving on Milk Production in Holstein Cattle written by Robert David Clark and published by . This book was released on 1960 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Environment on Nutrient Requirements of Domestic Animals written by National Research Council and published by National Academies Press. This book was released on 1981-02-01 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Heat Stress and Body Weight on the Performance Health Survival and Physiology of Holstein Dairy Cattle written by Longfei Han and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving heat-stressed animal health and survival through management, nutrition, and genetics is critical to profitability and sustainability on a dairy farm. The objectives of this dissertation were to estimate genetic parameters of heat tolerance in dairy cattle for the health and survival traits; to investigate the long-term impact of heifer development; and to examine the potential role of ghrelin in thermoregulation during heat stress. Five experiments were conducted and summarized. The first experiment investigated the effect of heifer development (measured as body weight at first calving, BWFC) on milk production and survival. First lactation 305-d milk yield and 24-month milk yield were analyzed with a linear model. Survival analysis was performed to estimate the impact of BWFC on survival. Heifers in the top 60% of body weight at first calving had significantly higher first lactation 305-d milk yield than lighter heifers, but no relationship of BWFC and first lactation 305-d milk yield existed within the top 60%. Relationships between BWFC and 24-month milk yield were not significant. Heifers with higher BWFC lost significantly more body weight in early lactation. While BWFC was a significant predictor of first lactation 305-d milk yield, it accounted for 3% of variation, suggesting that BWFC is not a primary contributor to variation in milk yield. Compared to the lightest heifers, heaviest heifers were 49% more likely to be culled at any given time. These data indicated that, among heifers managed similarly, heavier heifers produced more milk in first lactation than lighter heifers, but lost more BW, faced a higher risk of being culled, and did not produce more milk long-term. The second experiment examined 1), the effect of climatic conditions at birth on organic calf stayability to 365 d of age (STAY) and respiratory disease (RESP) by 365 d of age, and 2), the genetic parameters of organic Holstein calf heat tolerance (HT) for STAY and RESP. HT was defined as the rate of change in STAY and RESP when a calf was born under heat stress. The final dataset included 77,090 calves from 16 USDA certified organic farms and included 35,520 Holsteins for genetic analyses. Phenotypic data were combined with climatic data obtained from local weather stations based on the zip code. Phenotypic analyses were performed with a model that included THI, breed, diurnal THI variation (daily maximum THI -- daily minimum THI; DTV), contemporary group, breed, and genetic effects. Estimated breeding values were calculated for Holstein sires with more than 10 daughters in the dataset. By 365 d of age, 80% of the calves stayed in the herd, and 7% of the calves recorded at least one RESP. Calf STAY decreased and RESP increased when calves were born in THI over 65. The additive genetic HT effect was significant for STAY but not RESP. The heritability for STAY and RESP were 0.100 and 0.025, respectively. In conclusion, calf STAY, RESP, and HT for STAY were heritable in organic herds and can be improved through genetic selection. The third experiment investigated the genetic and environmental effect of heat stress at calving on organic cow health and survival. Health trait were mastitis, reproductive disease, disease during the transition period (TRAN); and stayability to 30 DIM (1 = stayed in the herd, 0 = culled or died by 30 DIM; STAY30). The final dataset included 83,394 lactations from 40,712 cows of 6 different breeds of which Holstein (32,007 lactations, 15,938 cows) were most frequent and were used for genetic analysis. Weather condition at calving was defined as cool (average THI
Download or read book Holstein Friesian World written by and published by . This book was released on 1922 with total page 1196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Relations Between Weight at First Calving and Milk Production During the First Lactation written by Robert H. Miller and published by . This book was released on 1958 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interrelationships Among Age Body Weight and Production Traits in Dairy Cattle written by David Arthur Harville and published by . This book was released on 1964 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Animal Breeding Plans written by Jay L. Lush and published by Read Books Ltd. This book was released on 2013-04-18 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: First published in 1943, “Animal Breeding Plans” contains a detailed guide on animal breeding designed for students with experience of genetics, embryology, breeds, and stock judging. It aims to furnish the reader with a clear understanding of the means available for improving the heredity of farm animals, especially what each possible method will or will not do well. Highly recommended for modern farmers and animal breeders. Contents include: “Origin and Domestication of Farm Animals”, “Consequences of Domestication”, “Beginning of Pedigree Breeding Methods in the United States”, “History of Animal Breeding Methods in the United States”, “Relation of the Breed Association to Breed Improvement”, “Genetic Principles in Animal Breeding”, “Mendelian Basis of Inheritance”, etc. Many vintage books such as this are increasingly scarce and expensive. It is with this in mind that we are republishing this volume now in an affordable, modern, high-quality edition complete with a specially-commissioned new introduction on farming.
Download or read book Dairy 2002 written by and published by . This book was released on 2004 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variation in Part and Whole Lactation Production Feed Intake Body Weight and Feed Efficiency for Holstein Cows written by Rex A. Sutton and published by . This book was released on 1975 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Breed Season of Calving Gestation Length of Preceding Dry Period and Body Weight Upon Milk Production in Georgia written by James Edmond Lee and published by . This book was released on 1960 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Designing Foods written by National Research Council and published by National Academies Press. This book was released on 1988-02-01 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: This lively book examines recent trends in animal product consumption and diet; reviews industry efforts, policies, and programs aimed at improving the nutritional attributes of animal products; and offers suggestions for further research. In addition, the volume reviews dietary and health recommendations from major health organizations and notes specific target levels for nutrients.
Download or read book The Ration and Age of Calving as Factors Influencing the Growth and Dairy Qualities of Cows written by Clarence Henry Eckles and published by . This book was released on 1915 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Yearling Weight on Fertility Measures in Holstein Heifers and Primiparous Cows written by Baneet Kour and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Canadian dairy industry consists of approximately 10,000 dairy farms with about 1.4 million head dairy cattle population, 70% of which are cows, and the rest are heifers. Cows constitute the productive segment of the herd, as they produce milk whereas the heifers form the non-productive segment. However, the heifers are equally important as they determine the future of the herd. After attaining puberty, the heifers become reproductively active and capable of replacing the dairy cows in the herd that may fail to reproduce or are culled from the herd. A producer should, therefore, select heifers with a good reproductive potential as replacements for the herd. Data from the Québec Dairy Herd Improvement Agency (Valacta) were analysed to determine the relationship between yearling weight in Holstein heifers and various fertility measurements in heifers and primiparous cows. The fertility parameters analyzed, depending on developmental stage included: Days to first service; Number of services for conception; Days from first to successful breeding; Days open; and Calving Interval (first to second calving). Since yearling body weights were rarely reported, yearling weight in heifers was predicted from available weight data, using the approach of Cue et al. (2012). The study covered a period of 8 years from 2008 - 2015, and the fertility parameters were analyzed as three groups: heifers that had a successful first calving; cows that had both a first and a second calving; and cows that had a first calving but failed to conceive a second time. Results showed that predicted yearling body weight had a significant effect on only some fertility traits of heifers; heifers that were predicted to weigh less than 300 kg at 12 months of age required a significantly fewer number of services to conception and had a significantly fewer number of days between first and successful breeding. In cows that failed to conceive the second time, the interaction between predicted weight at 12 months of age and age at first calving, had a significant effect on days to first service. Predicted body weight at 12 months did not have a significant effect on other fertility measures in those two data sets, and no significant effect on any of the fertility parameters in the data set of cows that that had both a first and a second calving. Not surprisingly, an earlier age at first calving had a significant effect on most first-lactation measures of fertility, as well as on days open and calving interval in cows that had both a first and a second calving. The data also demonstrated a considerable proportion of first calvers that failed to have a second conception. In conclusion, body weight at 12 months had no significant effect on post-first calving fertility measures. However, a lack of actual body-weight measurements in the data should not be overlooked (animals with no recorded weight prior to first calving could not receive a predicted body weight at 12 months), and this emphasises the importance of data recording for a better understanding of the dairy industry's reproductive challenges"--
Download or read book Raising Dairy Replacements written by Patrick C. Hoffman and published by . This book was released on 2003 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nutrition and Lactation in the Dairy Cow written by Philip C. Garnsworthy and published by Elsevier. This book was released on 2013-10-22 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrition and Lactation in the Dairy Cow is the proceedings of the 46th University of Nottingham Easter School in Agricultural Science. Said symposium was concerned with the significant advances in the field of nutrition and lactation in the dairy cow. The book is divided in five parts. Part I deals with the principles behind nutrition and lactation of cows. Part II discusses the cow’s nutrient interactions; responses to nutrients that yield protein and energy; and the influence of nutrient balance and milk yields. Part III tackles the efficiency of energy utilization in cows and its relation to milk production. Part IV talks about food intake of cows and the factors that affect it, while Part V deals with the different feeding systems for cows. The text is recommended for those involved in raising cows and dairy production, especially those who would like to know more and make studies about the relationship of nutrition and lactation of cows.
Download or read book Optimization of Age and Body Weight at First Calving for Milk Production in Dairy Cattle written by Suraj Bhan Singh and published by . This book was released on 1978 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Beltsville Growth Standards for Holstein Cattle written by C. A. Matthews and published by . This book was released on 1954 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
